Abstract
Purpose :
Peripheral retinal vascularization continues following treatment with bevacizumab (IVB) for type 1 Retinopathy of Prematurity (ROP). However, many eyes have persistent avascular retina (PAR) despite therapy, which may lead to late reactivation, retinal detachment, and blindness. We aimed to identify risk factors for PAR following bevacizumab therapy for type 1 ROP.
Methods :
We conducted a retrospective series of 106 eyes from 53 infants with type 1 ROP. 74 eyes from 37 infants received IVB with subsequent laser of PAR at an average of 49.5 weeks postmenstrual age (PMA) 95% CI [45.7, 53.2] (Group 1). 20 eyes from 10 infants were treated with IVB and did not receive subsequent laser (Group 2). Fundus photos were available for 52 eyes of 26 infants in Group 1 and from 14 eyes of 7 infants in Group 2. We compared the patient demographics, timing of treatment, and the fundus photographs at the time of IVB and laser photocoagulation. Length and rate of vascular growth after IVB were measured. In addition, we measured changes in vascular severity score (VSS) following IVB, which provides an objective assessment of disease severity.
Results :
The average length of vascular growth following IVB was 100.7 millimeters (mm), 95% CI [86.2, 115.1] over an average of 80.4 days, 95% CI [70.3, 90.4]. Group 2 had higher birthweight (BW) (p<0.05), greater extent of retinal vascularization at time of IVB (p<0.001), and lower VSS at time of IVB (p<0.01) than Group 1. Zone/Stage, gestational age (GA), and post-menstrual age (PMA) at time of IVB did not differ significantly between Group 1 and Group 2. The overall mean VSS decreased significantly following IVB in all Group 1 eyes (p<0.001). The amount of VSS change from time of IVB to time of laser was positively correlated with the extent of vascular growth following IVB (p<0.05), providing a potential biomarker for PAR.
Conclusions :
The presence of PAR requiring laser after IVB was associated with lower BW, more posterior disease, and higher VSS at the time of IVB. In addition, a larger VSS change following IVB was significantly associated with increased vascular growth. VSS may provide a tool for predicting PAR and monitoring for arrest of vascularization.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.